Burglar-alarm.



No. 812,420. PATENTED FEB. 13, 1906. F. G. HARRIMAN.

BURGLAR ALARM.

APPLICATION FILED SBPT.24,1904.

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No. 812,420. PATENTED FEB. 13, 1906. F. O. HARRIMAN.

BURGLAR ALARM APPLIGATION FILED SEPT. 24, 1904.

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rmrrsn STATES PATENT ornice.

FREDERICK'OJ HARRIMAN, OF YONKERS, NEW YORK.

BURGLAR-ALARWI.

Specification of Letters Patent.

Patented Feb. 13, 1906.

Application filed September 24, 1904. SerialNo. 225,739.

To ail whom itmay concern;

Be it known that I, FREDERICK C. HARRI- MAN, a citizenof the United-States, residing,

simple, compact, economical, and reliable del-- vice of this sort which may be readily placed in position to protect a door or window and which will be effective to alarm not only the occupants of the building, but the burglar as: To these ends the invention comprises.

well. a base designed for ready attachment to a floor or the stile of a window-frame, a hammer pivotedupon the base, an. anvil or means a for holdinga detonator, andmeans for cock ing the hammer and for enabling the opening movement of the door or window to cause the hammer to strike. Any suitable detonator may be used, preferably one giving a loud report, so as not only to arouse the occu pants of the house, but also to lead the bur glar to suppose that he is discovered and that a firearm has been shot at him, thereby frighteninghim away. Inits preferred form the base is 'constructed so-thatit is only necessary to set it upon thefloornearrthe door,

its construction being such that it cannot be. moved out of position by the opening of the door, whereby'it may be readily removed and replaced whenever desired.

In the accompanying drawings, Figure .1 is a perspectiveview of my improved burglar: alarm, showing the form adapted to rest upon a, floor, the hammer being cocked.v Fig. 2 shows the alarm placed upon the floor in position to be operated when the door opens, as indicated by the arrow. Fig. 3 shows the alarm being operated by the movement of the door. Fig. 4 is a longitudinal section showing the hammer in striking position. Fig. 5 is a plan showing the alarm placed upon a floor near a door, the hammer being cocked. Fig. 6 shows how the device may be attached to the stile of a window-frame in position to be operated by the opening move- :theexplosion of the detonator 10.

ment of a sashp Fig.7 is a modification oi the Fig. 6 construction.

The alarm is illustrated as comprising a base 1, provided with an anvil portion 2, a"

hammer. 3, and a hammer-driving spring 43 The base may be conveniently formed from a strip of sheet metal, from each end of which I may be bent downwardly and forwardly pro jecting prongs 5 6. Between the ends of the base the metal may be turned up to form opposite ears 7 8, between which the hammer 3 I is pivoted by means of a pin 9 insuch a manner that itmay strike forwardly and -downwardly upon a percussion-cap or other detonator l0, resting upon the anvil 2 andcon fined in .the pocketformed by the ears 7 8m 1 The. member 4,-Whi0l1 drives the hammer,

may be in the form of a leaf-spring or spring-' finger andzby means of a rivet 1 1 may be fixed at itsrearend to the rear'end of the base-andmay eXtendiorwardl-y andupwardly to rest uponthe hammer. The tip of the latter may be provided with a small boss 13,-and-the tip 1 of the spring maybe cupped'at 14 to'fit yield ingly' upon the rbossi-and 'hold' the hammer cocked. When the :parts are in this positionand the alarmais resting upon-the floor, the

rear end of the spring is lower and theforward 1 endlhigher thanthe loweredgeof a door, as at Fig. 2. When it is desired to set the alarm,- the hammer may be lifted,-flexing slightly the spring 4, until the cup 14 catches upon the boss '13. Then-a paperor other detonator 10 is set-upon the anvil 2 between ears 7 8,

- and the device is then set upon the fioor '15,

near a door 16, in such a position that-when" .thedoor is opened-the bottom-edge thereof Will engage the spring, as at Fig. 3, and'by a ,wedging action flex the same downwardly,

causing the cup 14 to slip offa'nd'release the the hammer down with great force, insuring rides downover the same to accelerate its 've .boss 13, and also causing the spring to drive The back locity .during its downwardmovement. When the door strikes the spring, it tends to push the alarm along the floor; but this tendency is resisted by the pron s 5 6, which point forwardly and downward so that the pressure caused by the door may cause the prongs to dig into the floor or carpet, for which purpose they may be sharpened, as illustrated. Thus it will be seen that the alarm may be inexpensively manufactured, is of few parts and reliable, may be readily set, is adapted to use common detonators, and requires no skill in its use, while capable of frightening a burglar away as well as of giving notice of his presence, and when it is unnecessary to protect the door the alarm may simply be picked up from the floor and set down by another door or put away until again needed.

At Fig. 6 the invention is shown as adapted to use upon a window, being attached to the stile 18 just above the sash 19, with the spring end lowermost, this end of the base being unprovided with the spurs 6 and being made sufiiciently thin to enable the sash to operate the spring without likelihood of binding in the window-frame. Usually there is sufficient space between the sash and the stile to accommodate the alarm, especially when the lower end thereof is made thin, as illustrated. The upper prongs 5 may be retained so that the sash may not force the alarm up along the stile, and a tack 20 may be used for securing the lower end of the base, the tack being preferably secured to the base during its manufacture. The upper end of the base may be similarly secured, as at Fig. 6, or the prongs 5 may be retained at said upper end, as at Fig. 7. The lower end of the base may be beveled or thinned, as at 21, to insure that the top corner of the sash while rising shall not catch and hold thereon. The action of the sash upon the spring 4 is substantially the same as that already described with reference to the door, the hammer being released and caused to strike by the fieXure of the spring due to the engagement of the sash therewith.

Other variations may be resorted to within the scope of my invention.

Having thus described my invention, I claim 1. A detonating burglar-alarm comprising a base, a hammer pivoted upon said base and having an arched back, and a spring fixed at one end upon said base in. rear of said hammer and inclining upwardly thereto and resting upon said arched back; means being provided for retaining the hammer in its raised position, the hammer being releasable by downward pressure upon the spring, and the tension of the spring caused by such pressure being effective to cause the hammer to strike.

2. A detonating burglar-alarm comprising a sheet-metal base having downwardlyturned prongs and upwardly-turned ears which form a pocket for holding a detonator,

a hammer pivoted between said ears, and a spring secured at its rear end to said base and inclining upwardly and forwardly and bearing upon said hammer; means being provided for enabling said spring to hold said hammer cooked, and the construction being such that .downward fieXure of the spring releases the hammer and causes it to strike.

3. A detonating burglar-alarm comprising a strip of sheet metal having at each end a pair of downwardly and forwardly turned prongs and near its forward end a pair of upwardly-turned ears which form a pocket for the reception of a detonator, an arched hammer pivoted between said ears and provided upon its tip with a boss, and a spring attached at its rear end to the rear of said strip and inclining upwardly and forwardly and having a cupped portion to fit over said boss for holding the hammer when cocked, the spring being of such a length that its tip rides down along the arched back of the hammer while the lat ter is striking.

4. A burglar-alarm comprising the combination of a base; a hammer pivotally mounted therein and a spring secured at its lower end to said base and having its upper free end overlapping the upperfree end of said hammer in the latters cocked position, the upper free end of said spring being formed with a retaining-recess for holding said hammer in cocked position.

5. A burglar-alarm comprising the combination of a base provided with retaining means; a hammer pivotally mounted in said base and actuated by a flat spring; and said flat spring one end of which is secured to the base and the other end of which overlaps and retains said hammer in cocked position; said hammer being released by pressure upon said spring and driven by said spring after such release.

6. In combination, a door; a base; a hammer mounted in said base; and an inclined spring-arm the lower end of which is secured to said base and the upper end of which is formed to engage and retain in cocked position said hammer; said door and base being movable relatively to each other, and said spring-arm being in the pathof travel of said door and actuated directly by the pressure of said door to release and drive said hammer against said base.

FREDERICK C. HARRIMAN.

Witnesses:

WARD W. PIOKARD, JULIEN T. DAVIES, Jr. 

